Definitive Technology BP9000 Series 5.4.4 Speaker Package Review

American muscle

SRP: £4,495.00

What is the Definitive Technology BP9000 Series

Definitive Technology might not be a name that you're immediately familiar with, but this US company has been building exceptional speakers since it first evolved out of Polk back in 1990. Def Tech – as the manufacturer is often referred to – is now part of the Sound United group that also includes Polk, Denon, and Marantz, and as a result, its products are now more widely distributed outside the States.

Def Tech has made a number of different products over the years, but speakers are what the company is best known for. The BP9000 Series has been available for a few years now, and perfectly represents the company's design philosophy. These floorstanding speakers are unlike anything you've seen before, with bipolar driver arrays and built-in subwoofers.

The BP9000 series includes four different floorstander models, three dedicated types of centre speaker, a pair of surround designs, and an upward-firing module for immersive audio systems. For the purposes of this review, I'm testing a system composed of two BP9040 floorstanders at the front, a CS9040 in the centre, and two BP9020 floorstanders for the surround channels.

To complete the set there are also four A90 upward-firing modules, creating a full 5.4.4-channel immersive audio system. That's one hell of a set-up, but I'd expect nothing less from our American cousins. So let's fire it up and find out what identical tweeters and drivers plus four subs can do in a big multichannel system.

Definitive Technology BP9040 Floorstanding Speaker

Definitive Technology BP9000 Series
The Definitive Technology BP9040 is an impressive looking beast with its bipolar driver array and built-in 8" subwoofer, but amazingly it's not the biggest floorstander in the range. There's also the BP9060 with an integrated 10" subwoofer, and the BP9080x which has a 12" sub and integrated height modules. It's fairly obvious that Def Tech has big American homes in mind when designing its speakers, but for the average UK dwelling, the BP9040s will do nicely.

This high performance floorstanding speaker comes in black and is built from high quality aluminium, which makes it sturdy but lighter than you might expect. The design is simple but I really like the minimalist aesthetic, with wrap-around fabric grilles, a solid aluminium base, and a removable brushed aluminium top plate. However, this speaker isn't just pretty, it also benefits from an incredible level of joined-up thinking on the part of Def Tech, proving the company has considered every aspect of design.

For a start, the aluminium base provides excellent support, ensuring the floorstander can't be easily toppled over. In addition, you have a choice of spikes or floor glides, allowing the BP9040s to be effectively used with carpets or hard flooring. The aluminium top plate is held in place with magnets and, when removed, it has a nice black velvet underside. Beneath the plate, you'll find a dedicated attachment for connecting the A90 upward-firing module.

This is the perfect example of Def Tech's clever approach to design, and it is backed-up by another very sensible feature. Since you attach the A90 at the top, at the bottom there are two pairs of 5-way gold-plated binding posts – one set is for the floorstander and the other is for the height channel being delivered by the attached A90. At the rear of the BP9040, along with the binding posts, there's a control for the bass level of the built-in subwoofer, and an LFE input.
Definitive Technology BP9000 Series
Once again, Def Tech has been very sensible, providing the option of running the speakers as large full-range models in a multichannel system, or setting them up as small and connecting the subwoofer output on your AV receiver/processor/amplifier to the LFE input on the BP9040. There's an illuminated LED logo at the front, which shows when the subs are actively engaged and receiving a signal. It automatically turns off after 20 minutes of no active signal, but you can permanently turn off the logo if you prefer.

The BP9040 is as unusual on the inside, as it is on the outside. The cabinet is designed to be inert and resonance-free, thanks to the aluminium construction and some strategically placed bracing, while the wrap-around fabric grilles are also acoustically transparent to ensure an uncoloured sound.

The BP9040 uses Def Tech's patented Forward-Focussed Bipolar Array (FFBP), which basically means it has a 1" aluminium tweeter and two 4.5" midrange drivers firing forwards, and a 1" tweeter and a 4.5" midrange driver firing backwards. The front array driver enclosure and the rear array driver enclosure both use acoustically tuned venting. The speakers also use Def Tech's Balanced Double Surround System (BDSS) to increase the output and dispersion, and make the midrange driver seem larger.

If that wasn't enough, the BP9040 also boasts an active 8" subwoofer integrated into the side of the cabinet, along with 300W of Class D amplification. Beneath the sub, there are two 8" bass radiators, one on the left and one on the right hand side of the cabinet. The speaker includes Def Tech's Intelligent Bass Control, which uses a 56-bit digital signal processor to give you the ability to adjust the bass level while simultaneously maintaining optimal midrange clarity regardless of where the bass control is actually set.

The Definitive Technology BP9040 has a nominal impedance of 8 ohms, a claimed sensitivity of 92dB, and a claimed frequency response of 22Hz to 40kHz. Since these speakers include an active subwoofer, you will need to plug them in using the provided three-pin power cables. The BP9040 measures 1022 x 330 x 330mm (HxWxD), weighs 16.33kg with the base attached, and costs £1,699 a pair.
They look gorgeous but their design also reveals a considerable level of thought

Definitive Technology CS9040 Centre Speaker

Definitive Technology BP9000 Series
The Definitive Technology CS9040 is a dedicated centre speaker that has been designed to tonally match the BP9040 floorstander. It's the smallest of Def Tech's 9000 Series centre speaker range, with the larger CS9080 and CS9060 both including an integrated 8" subwoofer, much like the company's floorstanders.

The CS9040 takes a slightly more traditional approach in terms of its driver layout, with a forward-firing enclosure containing 1" aluminium tweeter and two 4.5" midrange drivers. There's also Def Tech's Balanced Double Surround System (BDSS), and the CS9040 has an 8" bass radiator built into the top, while the enclosure has an acoustically tuned vent.
Definitive Technology BP9000 Series
The look of the CS9040 mirrors the rest of the BP9000 Series with aluminium construction, internal bracing and black wrap-around acoustically inert fabric. The build quality is excellent, the minimalist design is classy, and the brushed aluminium trim at either end is rather eye-catching. At the rear, you'll find a regular pair of 5-way gold plated binding posts.

The Definitive Technology CS9040 has a nominal impedance of 8 ohms, a claimed sensitivity of 89dB, and a claimed frequency response of 50Hz to 40kHz. The speaker measures 151 x 527 x 305mm (HxWxD), it weighs 9.07kg and retails for £499.
The centre speaker's driver array is designed to seamlessly blend with the BP9040

Definitive Technology BP9020 Floorstanding Speaker

Definitive Technology BP9000 Series
The Definitive Technology BP9020 is the smallest of the company's range of BP9000 Series floorstanders. However, it still boasts many of the same features as the larger BP9040. So it has a similar aluminium construction and internal bracing, resulting in a light but solid cabinet. There's a black wrap-around fabric grille, aluminium base with a choice of spikes or floor glides, and brushed aluminium top plate.

The BP9020 also retains all the same clever design features, so under the removable top plate, you'll find a connector for the optional A90 upward-firing module. At the rear, there's a bass control for the integrated sub, along with an LFE input, and a switch for turning off the front LED display. You also get two sets of 5-way gold-plated binding posts: one for the speaker and one for the A90 when it's attached.
Definitive Technology BP9000 Series
Aside from being slightly smaller, the BP9020 looks identical to its larger brother, but there are differences on the inside. The BP9020 has a built-in side-firing 8" subwoofer with 300W of Class D amplification, but no 8" passive radiators. However, there is Def Tech's Intelligent Bass Control, with its 56-bit digital signal processor for improved midrange clarity and bass management.

It also includes the same Forward-Focussed Bipolar Array (FFBP) with a forward-firing driver array that uses a 1" tweeter and two 4.5" midrange drivers, but the rear-firing array is limited to a single 4.5" midrange driver. However, it still uses Def Tech's Balanced Double Surround System (BDSS), and both the front and rear enclosures use acoustically tuned venting.

The Definitive Technology BP9020 has a nominal impedance of 8 ohms, a claimed sensitivity of 92dB, and a claimed frequency response of 28Hz to 40kHz. As with the BP9040, you will need to plug the integrated sub in using the provided three-pin power cables. The BP9020 measures 934 x 330 x 330mm (HxWxD), weighs 13.61kg with the base attached, and costs £1,299 a pair.
By using floorstanders at the front and rear, the system is based around four subs

Definitive Technology A90 Dolby Atmos/DTS:X Module

Definitive Technology BP9000 Series
The Definitive Technology A90 is an upward-firing module intended for both Dolby Atmos and DTS:X immersive audio formats. The speaker itself is another example of Def Tech's intelligent design, combining ease of installation with a seamless appearance once attached.

The speaker itself uses the same aluminium construction and black wrap-around fabric grille as the rest of the BP9000 range, and there's an attractive brushed aluminium trim at the top. It's well made and on the underside there's a velvet finish, which is another nice touch.
Definitive Technology BP9000 Series
The A90 fits perfectly on top of the BP9046 and BP9020 using its dedicated connector, which creates a totally seamless design. Then all you need to do is attach the speaker cable for that particular height channel to the binding posts at the bottom of the floorstander.

The sloped baffle and foam construction are designed to fire sounds towards the ceiling, which then reflect down towards the listener. The A90 uses the same 1" tweeter and 4.5" midrange driver as the rest of the BP9000 Series range, thus ensuring a degree of tonal balance.

The Definitive Technology A90 has a nominal impedance of 8 ohms, a claimed sensitivity of 89.5dB, and a claimed frequency response of 86Hz to 40kHz. The speakers measure 95 x 152 x 330mm (HxWxD), weigh 2.72kg and retail for £499 a pair.
The A90 is the ideal upward-firing module – easy to install and seamless in appearance

How was the BP9000 Series tested?

Definitive Technology BP9000 Series
The Definitive Technology BP9000 Series might look intimidating, but it's surprisingly easy to set-up. For a start the floorstanders aren't as big as you might expect, in fact they're surprisingly slimline. I attached the aluminium stands and spiked feet, and then placed the BP9040s at the front left and right positions either side of my screen. I then placed the BP9020s to the side and rear, behind the main listening position.

I removed the top plates and attached the four A90s to the top of all the floorstanders. I placed the CS9040 on a speaker stand at the front of the room, under the screen and halfway between the BP9040s. I then wired up the various channels, which in this case was front left, right, and centre; left and right surround; left and right front height; and left and right rear height. I also needed to plug all four floorstanders into wall sockets to power the integrated subwoofers.
Definitive Technology BP9000 Series
This is where things get interesting because I now had four subwoofers (one in each corner), rather than my usual two at the front. In theory this should result in an extremely balanced bass response because a sub in each corner of a room is normally considered ideal. I ran the system in two different configurations: in the first, I set all the floorstanders to large; and in the second I set the front two to small and connected the integrated subs using the sub outs on my AV receiver and the LFE inputs on the speakers.

I set the bass controls on the floorstanders to their halfway points, which seemed to work well, and then I performed a basic set-up and selected a crossover of 80Hz for the speakers set to small. I use an Arcam AVR850 as my reference AV receiver, but I deliberately chose not to use Dirac Live for this review because I wanted to test the uncorrected performance of the speakers. The overhead channels were driven using an Arcam P429 power amplifier and my primary source was the Oppo UDP-203 4K Blu-ray player. I tested the system using a mixture of material ranging from Blu-ray and Ultra HD Blu-ray, DVD-A, and SACD.
Aside from squeezing all this kit into my home cinema, set-up was relatively easy


Definitive Technology BP9000 Series
The Definitive Technology BP9000 Series is nothing short of a revelation, and in part that's because of the company's unusual approach to speaker design. The Forward-Focussed Bipolar Array (FFBP) is intended to replicate how sound is generated in nature. By firing drivers in opposite directions, there's a more spacious soundstage and a wider sweet spot. This is particularly helpful when trying to create an immersive system, but it does mean you really need a bit of space for these speakers to perform at their best. That's fine in a big US home, but can be more of an issue here in the UK.

What I particularly like about the BP9000 series is that all the speakers use exactly the same 1" aluminium tweeters and 4.5" midrange drivers. This means there's excellent tonal balance across the entire system, and while each speaker doesn't sound exactly the same, it does mean the sense of immersion is fairly seamless. The tweeter handles the higher frequencies superbly, and the midrange is wonderfully precise and detailed. I also like Def Tech's Balanced Double Surround System (BDSS) which makes the speakers sound even bigger than they actually are.

The A90's proved very effective when it came to generating the overhead channels, but there are some caveats. The ideal approach to multi-channel immersive audio is to install actual speakers on the ceiling. However, this is often impractical, which is why speaker manufacturers like Def Tech offer upward-firing modules such as the A90. The effect can be surprisingly believable but, for optimum performance, you need a relatively low and flat surface for the upward-firing sounds to reflect off. This approach doesn't work in all rooms (if you've got vaulted ceilings, forget it) but in the right environment it's an acceptable compromise.

The fact the A90s are so unobtrusive is a real bonus, and I don't know why other speaker manufacturers don't follow suit. The way the A90's connect at the top, and then you wire them at the bottom of the floorstander is nothing short of genius. The integration of 8" subwoofers is also really clever, and means that you can have multiple subs in your room without taking up more space (just don't forget you'll need to plug them in somewhere). The fact I had subs in every corner made a noticeable difference to the bass performance in my room. I generally found I preferred running the floorstanders as full-range large speakers, rather than using the LFE input, but that was very effective as well.
Definitive Technology BP9000 Series
I started my testing with some 5.1-channel music, just to shake off the cobwebs and get the system loosened up. I listened to Yoshimi Battles the Pink Robots by The Flaming Lips on DVD-Audio, and Pink Floyd's Dark Side of the Moon on SACD.

In both cases, the BP9000 system really impresses, with a big and dynamic performance that creates a fantastic sense of aural envelopment. The five speakers blend together seamlessly, creating a detailed and highly articulate soundscape that renders the individual instrumentation with precision.

The various sound effects that both albums employ are steered from speaker to speaker with no discernible change in their sonic signature. However, what really blew me away was the bass, which is incredibly tight and responsive. The drums have fantastic kick to them and the four floorstanders work in unison to keep the bass deep and balanced.

The system's handling of 5.1-channel music had simply whetted my appetite for something even more immersive, so it was time to bring the A90s into the equation. As I mentioned earlier, the success of these upward-firing modules does depend on your type of ceiling, but when done properly it really does sound as though effects are emanating from the ceiling.

Just to check the effectiveness of the BP9000 system with immersive audio, I ran through a few of my favourite trailers and tests on the Dolby Atmos demo disc. I immediately had helicopters flying overhead, and 747s taking off in front of me. Once I was happy that everything was performing as it should, it was time to pop on some demo-quality film soundtracks.

A Quiet Place is one of my current favourites and the exceptional Dolby Atmos mix is the perfect test for any system. The Def Tech handles it with genuine skill, reproducing all the tiny sound effects that punctuate the long periods of silence in the film. What's more, the system is able to handle the sudden changes in volume, and the ensuing dynamic range gives the film's scares greater impact.

The entire 5.4.4 system has an open and realistic presence that delivers the wind blowing through the trees or the sound of people's breathing with a pleasing accuracy. When the monsters appear, there is some powerful bass that the floorstanders deliver with amazing control, and the movement of a monster overhead is handled well by the A90s.

So far so good, but there was no way I was going to miss watching Jurassic Park in DTS:X while I had four subwoofers in my home cinema, and neither the film nor the system disappointed. The bass effects that herald the arrival of the T-Rex are handled with spine-tingling skill and the entire room is energised with low frequencies. Once she makes her unforgettable entrance, the four subs ensure that the dinosaur's sheer size and weight are delivered with a real sense of scale. The roar is utterly terrifying, with the entire frequency range being used.

The system never sounds bright or strained, even when you drive the speakers hard or crank up the volume. The atmospheric effects are also expertly delivered, from the thunder overhead to the rain hitting the car windshields, but dialogue is always clear and focused. These speakers have a clarity and neutrality that lends itself to film soundtracks, but they can also be a lot of fun which is an element that should never be underestimated.

If you really want to test the bass performance of a system, then Overlord with its Dolby Atmos soundtrack is the perfect choice. The opening parachute drop is handled with real gusto, thanks to four floorstanders, four subs, and plenty of power. The explosion that tears through the plane hits with a visceral impact, as does the flak exploding all around. Effects are steered around the room with incredible precision, and the BP9020s ensure that surround effects are delivered with as much weight as the rest of the channels.

The driving score is reproduced with relentless power, while the percussive kick from the heavy machine-gun fire hammers me into submission. This BP9000 can handle the subtlety of A Quiet Place with an exacting precision, but it can also deliver the over-the-top horrors of Overlord with a pleasing enthusiasm. However, despite the massive amounts of bass in this soundtrack, the subs never overpower the rest of the channels, instead integrating perfectly for a supremely balanced and enjoyable experience.
This system was a revelation, with a sound that was detailed, precise and immersive



  • Fantastic sound quality
  • Great tonal balance and bass
  • Clever design and features
  • Easy to setup and tidy
  • Attractive and well made


  • Needs space for best results

Definitive Technology BP9000 Series 5.4.4 Speaker Package Review

Definitive Technology BP9000 Series Verdict

The Definitive Technology BP9000 Series is an absolutely cracking system built around four superb floorstanders. While that might sound like overkill, these cleverly designed speakers have an elegant footprint that can blend into a room with ease. They look classy and sound even better, thanks to a bipolar driver array and integrated subwoofers.

There's a wonderful sense of openness and realism to the speakers, and they also allow you to build a system with subs in every corner of the room without taking up additional space. The result is superbly balanced bass that has impact but never overpowers the rest of the system. Once you add the centre speaker and four upward-firing modules you have a tonally matched system that can move sounds seamlessly from one speaker to the next.

What impresses about this system isn't just the looks and performance, as good as they are, but the amount of thought that Def Tech has put into every aspect of the system's design. The way the A90s slot into the top of the floorstanders, while the speaker cable is connected at the bottom is genius. The same goes for the integrated subs, which you can either run as part of the speaker or completely separately.

While £4,495 isn't exactly cheap, when you consider all that you get for your money, this BP9000 system is actually surprisingly good value. Definitive Technology is a brand that is worth checking out, and the BP9000 Series comes highly recommended.

What are my alternatives?

There aren't many immersive audio systems that come close to the Def Tech BP9000 for performance, and even less that offer the same clever design and features. However, the Elipson Prestige Facet 7.2.4 system is certainly worth considering. It's beautifully made and sounds fantastic thanks to a pair of excellent floorstanders at the front, an effective centre speaker, and four impressive surround speakers.

At £3,500 it's also cheaper, and the two subwoofers handle the low-end without breaking a sweat, while the four surrounds and four upward-firing modules ensure a very immersive experience. However, although the upward-firing modules fit snugly on top of the floorstanders, the same can't be said for the surrounds. That's when you realise just how clever and well-thought-out the BP9000 Series really is.

MORE: Read All Surround Sound Speaker Package Reviews

Highly Recommended


Sound Quality


Build Quality


Value For Money




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